Arc-light carbon.



UNITED STATES PATENT OFFICE.

AUGUST KUFFERATH, OF BEUEL, NEAR BONN, GERMANY, ASSIGNOR TO .stances int L. o. MARQUART, 0F BEUEL,

NEAR BONN, GERMANY.

ARC-LIGHT CARBON.

Patented Jan. 1, 1 907.

To all whom it may concern.-

Be it known that I, AUGUST KUFFERATH, chemist, a subject of the German Emperor, residing at Beuel, near Bonn-on-the-Rhine, Germany, have invented certain new and useful Improvements in and Relating to Arc- Light Carbons, of which the following is a specification.

I do hereby declare the nature of this invention and in What manner the same is to be performed to-be particularly described and ascertained in and by the following statement:

It has been ascertained by means of scientific experiment that the actinic power of the electric arc is affected to a considerable extent by the presence of certain metallic sube carbons. The actinic intensity, which is quite independent of the intensity of the light, is a formation of the atomic weight. If the actinity of an arc roduced between pure carbon is taken as t e standard, it is easy to reduce it below this stand 7 ard or to raise it above the same by the addition of suitable metallic compounds to the materials of which the carbons are composed.

I have found that an extremely high actinity can be very easily obtained by the use of a combination of two metallic salts, Which, moreover, need be employed only in proportions so small as to insure that the carbons will burn quietly and Without the formation of a slag. This metallic combination consists of amixture of equalparts, by Weight, of yttrium nitrate and lead nitrate, of Which not more than one-half per cent. should be added to the material of Which the carbons are com osed. Carbons prepared in the manner eretofore described burn quietly and without the production of slag and yield a light rich in violet rays and Which can be used With great advantage for light-therapeutics and photographic purposes. While I these carbons do not differ from others with respect to luminosity and current consumption, they are considerably superior With reference to their actinic power.

Having now particularly described and ascertained the nature of my said invention and in What manner the same is to be performed, I declare that What I claim is- Arc-light carbons for the production of a powerful actinic light, characterized by the fact that there is added to the carbon onehalf per cent. of a metallic combination, Which consists of equal parts by weight of yttrium nitrate and lead nitrate.

In testimony whereof I have hereunto set my hand in presence of two subscribing Witnesses.

AUGUST KUFFERATH.

Witnesses:

BEssIE F. DUNLAP, LoUrs VANDORY. 

